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Which of the fallowing best completes the sequence 5,10,15, a) 30 b) 22 c)25 d)35

The number of revolutions of two pulleys is inversely proportional to their diameters. if a 24-inch diameter pulley making 400 revolutions per minute is belted to an 8-inch diameter pulley, find the number of revolutions per minute of the smaller pulley.

If x=-3 is the only x-intercept of the graph of a quadratic equation, which statement best discribes the discriminant of the equation?